I have a max jax. You have anchors in the floor, which the towers bolt to.
You are supposed to have a minimum 4" slab of high pressure concrete, or failing that, a 12" concrete anchor. It is all specified in the instructions, it is all very safe but your garage may require some retrofitting if not poured properly. Most modern homes would have the proper concrete in the garage.
The system is very safe and frankly much safer than a jack / Jack stands which are not anchored to the floor.
The whole system is built to a standard worthy of use in a professional shop.
If for whatever reason the system would fail, you would get so much advanced notice with noise, cracking concrete, wobbling car, that you would have plenty of time to get out. And because you aren't lying on your back doing the work, your ability to get out quickly would be easy.
I mean, I know of three second hand stories of LBC owners getting crushed under their cars while lying on their backs with the car up on jack stands?
No thanks, I'll take the Max Jax.
Alan